Stapler



FIG. 1 is a rear perspective view of a stapler showing our design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof; and,

FIG. 6 is a right side elevational view thereof; the left side elevational view being a mirror image thereof.

The broken lines in the Figures are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a stapler, as shown and described. 